Graphene-copper coated electrical contact

Abstract

An electrical contact including a substrate of an electrically conductive material, and a graphene-copper composite coating on the substrate. The graphene content in the coating is within the range of 0.1 to 2 wt %.

1 . An electrical contact comprising:
 a substrate of an electrically conductive material; and   a graphene-copper composite coating on the substrate;   wherein the graphene content in the coating is within the range of 0.1 to 2 wt %.   
     
     
         2 . The contact of  claim 1 , wherein the coating is free of silver. 
     
     
         3 . The contact of  claim 1 , wherein the substrate material is or comprises copper and/or aluminium, preferably wherein the substrate material is copper. 
     
     
         4 . The contact of  claim 1 , wherein the graphene is in the form of sheets having a thickness within the range of 1-50 nm. 
     
     
         5 . The contact of  claim 4 , wherein the sheets have a longest diameter within the range of 5-80 μm. 
     
     
         6 . The contact of  claim 1 , further comprising:
 a pure copper coating on top of the composite coating.   
     
     
         7 . A contact arrangement comprising at least one electrical contact including a substrate of an electrically conductive material; and
 a graphene-copper composite coating on the substrate;   wherein the graphene content in the coating is within the range of 0.1 to 2 wt %.   
     
     
         8 . The contact arrangement of  claim 7 , wherein the contact arrangement is configured for a nominal voltage of at most 70 kV. 
     
     
         9 . The contact arrangement of  claim 7 , wherein the contact arrangement is a power connector. 
     
     
         10 . The contact arrangement of  claim 7 , wherein the contact arrangement is a switch-disconnector. 
     
     
         11 . A method of coating the substrate for the electrical contact including a substrate of an electrically conductive material; and
 a graphene-copper composite coating on the substrate;   wherein the graphene content in the coating is within the range of 0.1 to 2 wt %, the method comprising:   providing a graphene-copper electrolytic solution including graphene and copper ions; and   coating the substrate by electrodeposition whereby the graphene and copper ions are co-deposited to form a graphene-copper composite coating on the substrate;   wherein the graphene content in the solution is within the range of 0.01-1.5 g/L.   
     
     
         12 . The method of  claim 11 , wherein the copper ions are provided from a copper salt dissolved in the electrolytic solution, the salt including CuSO 4  and/or CuCl 2 . 
     
     
         13 . The method of  claim 12 , wherein the copper salt content in the solution is within the range of 50-250 g/L. 
     
     
         14 . The method of  claim 11 , further comprising:
 providing a copper electrolytic solution including copper ions; and   coating the graphene-copper composite coating by electrodeposition whereby the copper ions are deposited to form a pure copper coating on top of the composite coating.   
     
     
         15 . The contact of  claim 2 , wherein the substrate material is or comprises copper and/or aluminium, preferably wherein the substrate material is copper. 
     
     
         16 . The contact of  claim 2 , wherein the graphene is in the form of sheets having a thickness within the range of 1-50 nm. 
     
     
         17 . The contact of  claim 2 , further comprising:
 a pure copper coating on top of the composite coating.   
     
     
         18 . The contact arrangement of  claim 8 , wherein the contact arrangement is a power connector. 
     
     
         19 . The contact arrangement of  claim 8 , wherein the contact arrangement is a switch-disconnector.